In a server-client system, it has been carried out to date that when a sever recommends a certain item, such as a book, a television program, etc., to the user of a client apparatus, a recommendation reason, together with the information on the recommended item, has been displayed onto the screen of the client apparatus.
The recommendation reason is displayed, for example on the basis of the following two methods.
1. Collaborative Filtering
For the user who has selected a certain book, the server apparatus recommends the books in which the other people who have selected the same book as that user or the other people who have the same preferences are interested, and presents the reason, such as “Those who selected the book you have selected also have purchased the book XXX in addition”.
That is to say, here, for the recommendation reason of “the book XXX”, the fact that the purchases have been made by those who selected “this book” similarly as the user who is currently being recommended the book.
2. Presentation by Highlighting the Word that has Served for Recommendation
For example, when the user, who is going to receive a recommendation of programs, often views sports programs (when the server apparatus obtains the viewing history of the client apparatus), the server application recommends sports programs, and presents a reason, such as “These are “sports” programs in the category you often view.””
That is to say, here, for the recommending reason of a certain sport program, the fact that the category of the programs the user often views and the category of the recommended programs are “sports”, which are the same, is shown.
In the same manner, when the user who is going to receive a recommendation has an interest in travels (when the server apparatus obtains, in advance, the information that the user is interested in travels by getting replies to a questionnaire, etc.), the server apparatus recommends hot-spring tour programs, and presents the reason, such as “The keywords of the programs you often view are a “hot spring”, “health”, and a “travel”.
That is to say, here, for the recommendation reason of a certain hot-spring tour program, the fact that the contents of the program are related to a “hot spring”, “health”, and a “travel” in which the user is interested is shown using the keywords.
The technique of presenting a recommendation reason of programs has been disclosed in Japanese Unexamined Patent Application Publication No. 2004-355340. Also, the importance of teaching a reason when something is recommended to a person has been disclosed in the non-patent document as follows: Jonathan L. Herlocker, Joseph A. Konstan, and John Riedl Dept. of Computer Science and Engineering University of Minnesota Explaining Collaborative Filtering Recommendations